The present disclosure relates to a key of a keyboard instrument.
A plastic key of an electronic piano is formed into a shape having an open lower portion for the purpose of facilitating molding. On an inner side of the key, a plurality of ribs are provided in order to increase an overall strength of the key. Thus, the key has such an appearance that a plurality of holes are open downward.
An invention has been disclosed in which a weight is attached to one of a plurality of holes provided in a key, so as to adjust touch feeling of the key. The weight described, for example, in Japanese Unexamined Patent Application Publication No. 2015-114597 is entirely formed of an elastic material such as rubber. The weight has a main body formed into a rectangular parallelepiped shape, and a plurality of pleats provided on the main body.
The weight is cut in such a manner that its weight matches touch feeling of each key and is pushed into the hole of the key.
Upon pushing in, each of the pleats is bent in an opposite direction to a pushing direction. Therefore, the weight, when pushed into the hole of the key, is stretched inside the hole by a restoring force due to the bending of the pleats, and is retained so as not to escape from the hole.